It is becoming more common to use a biometric signature of a subject as a way of securely identifying (authenticating) the subject. A biometric signature is a collection of biometric parameters sensed by a biometric sensor.
A strong biometric signature may be a physiological feature or collection of features which is stable, unique to a particular subject, detectable and not easily reproduced by another person. Examples of biometric signatures include, for example, an iris scan, a fingertip scan, an electrocardiogram.
One problem with using biometric signatures is that the processing of the biometric parameters to determine the biometric signature and the processing of the biometric signature to authenticate a subject can be relatively power-intensive, which can make biometric signatures unsuitable for subject authentication in low-power environments.